1. Field of the Invention
The invention relates to metal cable traction apparatus in which a pair of self-tightening clamps connected to a crank-shaft act on the cable according to a reciprocating movement.
2. Description of the Prior Art
Such apparatus are already known, notably according to U.S. Pat. No. 2,585,101 which comprise two kinematic connections each actuated by a separate lever, the one performing the hauling movement and the other performing the release movement.
According to U.S. Pat. No. 3,995,830 the release kinematic connection comprises a pair of rocking levers pivoted respectively at one end to control links of one clamp and interconnected at their other ends through a rod, one of the rocking levers called the release control rocking lever being actuated for a translation movement under the action of the release control lever while the other rocking lever is actuated according to a rotation movement under the effect of the reaction exerted in its middle portion by a link pivoted to a fixed point.